#ifndef Yamada
#define Yamada
#include Yamada __FILE__ Yamada

const int mod = 998244353;

void solve() {
    int n, m; cin >> n >> m;
    int ans = n - m + 1;
    for (int i = 1; i < m; ++i) {
        ans = ans * (n+1) % mod;
    }
    cout << ans << '\n';
}

signed main() {
    IOS();
    int t = 1; // cin >> t;
    for (int i=1;i<=t;++i) solve();
    return 0;
}

#else

#ifdef local 
#define _GLIBCXX_DEBUG 1
#endif
#pragma GCC optimize ("Ofast", "unroll-loops")
#include <bits/stdc++.h>
using namespace std;

#define int int64_t
// #define double __float80
using pii = pair<int, int>;
template <typename T> using MaxHeap = std::priority_queue<T>;
template <typename T> using MinHeap = std::priority_queue<T, vector<T>, greater<T>>;

#define SZ(a) ((int)(a).size())
#define ALL(a) begin(a), end(a)
#define RALL(a) rbegin(a), rend(a)
#define ee emplace
#define eb emplace_back
#define ef emplace_front
#define pb pop_back
#define pf pop_front
// #define X first
// #define Y second

#ifdef local
#define IOS() void()
#define debug(...) \
    fprintf(stderr, "\u001b[33m"), \
    fprintf(stderr, "At [%s], line %d: (%s) = ", __FUNCTION__, __LINE__, #__VA_ARGS__), \
    _do(__VA_ARGS__), \
    fprintf(stderr, "\u001b[0m")
template <typename T> void _do(T &&_t) {cerr << _t << endl;}
template <typename T, typename ...U> void _do(T &&_t, U &&..._u) {cerr << _t << ", ", _do(_u...);}
#else
#define IOS() ios_base::sync_with_stdio(0); cin.tie(0)
#define debug(...) void()
#define endl '\n'
#endif

template <typename U, typename V> bool chmin(U &u, V v) {return u > v ? u = v, 1 : 0;}
template <typename U, typename V> bool chmax(U &u, V v) {return u < v ? u = v, 1 : 0;}

#endif